Carbothermal synthesis of porous silicon carbide using mesoporous silicas

• Published in: Journal of materials science 2017-04, Vol.52 (7), p.3917-3926
• Main Authors: Shcherban, Nataliya D., Filonenko, Svitlana M., Yaremov, Pavel S., Sergiienko, Sergii A., Ilyin, Volodymir G., Murzin, Dmitry Yu
• Format: Article
• Language: English
• Subjects: Adsorption; Carbon; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Hydrogen; Materials Science; Molecular sieves; Original Paper; Polymer Sciences; Porous materials; Porous silicon; Silicon; Silicon carbide; Silicon carbides; Silicon dioxide; Solid Mechanics; Sucrose; Surface chemistry
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-016-0652-7

Samples of crystal modifications of porous silicon carbide were obtained by carbothermal method using carbon precursors (sucrose, carbon) and aerosil or mesoporous silicas molecular sieves SBA-3, SBA-15, KIT-6, and MCF as silicon sources. Porous β -SiC samples obtained from carbon–silica composites are characterized by high structural and sorption characteristics ( S BET up to 410 m 2 /g, V pore up to 1.0 cm 3 /g). High hydrogen adsorption capacity of silicon carbide samples based on KIT-6 (up to 1.24 wt% at 77 K and 1 atm.), considering low adsorption energy ( Δ μ 0 H 2 ) up to 2.3 kJ/mol for SiC vs. ca. 5.0 kJ/mol for carbon), was determined. The highest ever reported value among the existing porous materials was observed for specific adsorption of H 2 by SiC (specific adsorption on the pore surface, ρ up to 15 μmol/m 2 ) corresponding to almost complete filling of the surface with hydrogen in the examined conditions (77 K, 1 atm.).